Systemic Sclerosis in Individuals With Exposure to World Trade Center Ground Zero Rescue and Recovery Efforts: A Case Series.

OBJECTIVE: The World Trade Center (WTC) attack in New York resulted in a dust plume containing silica, hydrocarbons, and asbestos. Autoimmune disorders have been reported among those with WTC site exposure. The characteristics of individuals developing systemic sclerosis (SSc) have not been previously described. The purpose of this study was to describe the features of patients with SSc with WTC exposure. METHODS: Data were collected from 11 patients with SSc or SSc spectrum conditions who reported exposure to the WTC site. Seven patients completed an exposure assessment. RESULTS: Of the 11 patients, the majority (n = 8) were female. The median (range) for age at diagnosis was 46 (36-75) years, time between exposure and first non-Raynaud phenomenon SSc symptom was 8 (1-19) years, and time between exposure and diagnosis was 11 (2-18) years. Fifty-five percent had SSc onset > 5 years from WTC exposure. Five patients had limited cutaneous SSc, 3 patients had diffuse cutaneous SSc, 1 patient with SSc features met criteria for mixed connective tissue disease (CTD), and 2 patients had undifferentiated CTD with features of SSc. Four patients had overlapping features with other CTDs. Interstitial lung disease (ILD) was present in 10 patients. Five of 11 patients had a history of tobacco use. Seven of 7 patients who completed the questionnaire reported other hazardous exposures outside of WTC. Of these, only 2 patients reported personal protective equipment use. CONCLUSION: A high frequency of ILD and overlap features were observed among patients with SSc with WTC exposure. Future studies are needed to characterize this association.

IKZF1 and UBR4 gene variants drive autoimmunity and Th2 polarization in IgG4-related disease.

IgG4-related disease (IgG4-RD) is a systemic immune-mediated fibroinflammatory disease whose pathomechanisms remain poorly understood. Here, we identified gene variants in familial IgG4-RD and determined their functional consequences. All 3 affected members of the family shared variants of the transcription factor IKAROS, encoded by IKZF1, and the E3 ubiquitin ligase UBR4. The IKAROS variant increased binding to the FYN promoter, resulting in higher transcription of FYN in T cells. The UBR4 variant prevented the lysosomal degradation of the phosphatase CD45. In the presence of elevated FYN, CD45 functioned as a positive regulatory loop, lowering the threshold for T cell activation. Consequently, T cells from the affected family members were hyperresponsive to stimulation. When transduced with a low-avidity, autoreactive T cell receptor, their T cells responded to the autoantigenic peptide. In parallel, high expression of FYN in T cells biased their differentiation toward Th2 polarization by stabilizing the transcription factor JunB. This bias was consistent with the frequent atopic manifestations in patients with IgG4-RD, including the affected family members in the present study. Building on the functional consequences of these 2 variants, we propose a disease model that is not only instructive for IgG4-RD but also for atopic diseases and autoimmune diseases associated with an IKZF1 risk haplotype.

Saddle Nose Deformity in a Patient With Crohn's Disease.

Crohn's disease is a chronic inflammatory disorder of the gastrointestinal tract, frequently presenting with extraintestinal manifestations. Granulomatosis with polyangiitis is a systemic vasculitis primarily affecting the respiratory tract and kidneys. Extraintestinal Crohn's disease and granulomatosis with polyangiitis may have similar clinical presentations and, in rare occurrences, can coexist. This case report highlights the diagnostic and therapeutic complexities of this uncommon overlap syndrome.

The CCT chaperonin is a novel regulator of Ca2+ signaling through modulation of Orai1 trafficking.

Store-operated Ca2+ entry (SOCE) encodes a range of cellular responses downstream of Ca2+ influx through the SOCE channel Orai1. Orai1 recycles at the plasma membrane (PM), with ~40% of the total Orai1 pool residing at the PM at steady state. The mechanisms regulating Orai1 recycling remain poorly understood. We map the domains in Orai1 that are required for its trafficking to and recycling at the PM. We further identify, using biochemical and proteomic approaches, the CCT [chaperonin-containing TCP-1 (T-complex protein 1)] chaperonin complex as a novel regulator of Orai1 recycling by primarily regulating Orai1 endocytosis. We show that Orai1 interacts with CCT through its intracellular loop and that inhibition of CCT-Orai1 interaction increases Orai1 PM residence. This increased residence is functionally significant as it results in prolonged Ca2+ signaling, early formation of STIM1-Orai1 puncta, and more rapid activation of NFAT (nuclear factor of activated T cells) downstream of SOCE. Therefore, the CCT chaperonin is a novel regulator of Orai1 trafficking and, as such, a modulator of Ca2+ signaling and effector activation kinetics.